ENYO-2899, ENYO-2074, ENYO-1503, ENYO-1768: update documentation
ENYO-2074, ENYO-1503: fix minify using enyo.loader from app

Rather use the one aside minify itself.
ENYO-1503, ENYO-1768: deploy|minify: any path but outDir is now relative

This fixes broken relative path minification (both CSS & JS) when the
output directory is not located onto the source tree.